Support for mounting small parts in electroplating processes

ABSTRACT

Frame for supportingly securing number of small parts each having circular edge of perforation parallel with a supporting surface while parts are subjected to electrodeposition treatment comprises electrically conductive main structure and holds for each part to be treated. Main structure includes at least one electrically conductive metal web, and each holder comprises plurality of non-electrically conducting rods which converge toward point and which engage circular edge or perforation of parts to be treated. At least one resilient rail is constructed and arranged to press holders carrying parts to be treated against metal web.

H. RITZENHOFF 3,785, SUPPORT FOR MOUNTING SMALL PARTS IN ELECTROPLATING PROCESSES Filed Oct. 30. 1972 kw J0 United States Patent O 3,785,952 SUPPORT FOR MOUNTING SMALL PARTS IN ELECTROPLATING PROCESSES Hermann Ritzenhoff, Marburg-Lahn, Germany, assignor to Gerbruder Seidel KG, Marburg-Lahn, Germany Filed Oct. 30, 1972, Ser. No. 302,120 Int. Cl. C23b 5/ 70 US. Cl. 204-297 W 24 Claims ABSTRACT OF THE DISCLOSURE Frame for supportingly securing number of small parts each having circular edge of perforation parallel with a supporting surface while parts are subjected to electrodeposition treatment comprises electrically conductive main structure and holders for each part to be treated. Main structure includes at least one electrically conductive metal web, and each holder comprises plurality of non-electrically conducting rods which converge toward point and which engage circular edge or perforation of parts to be treated. At least one resilient rail is constructed and arranged to press holders carrying parts to be treated against metal web.

BACKGROUND OF THE INVENTION The present invention relates to a frame for sup portingly securing a large number of small parts having a circular edge or perforation parallel with a supporting surface while the parts are subjected to electro-deposition treatment. The frame comprises an electrically conductive main structure with an electrically conductive bar secured thereto for carrying the products, and product holders for each part to be treated.

It is well known that the art of electro-deposition is concerned with the electrolytic deposition of metal upon metallic workpieces or upon non-metallic workpieces that are rendered conductive. Also, electro-deposition involves the electrolytic production of oxide surfaces, this latter treatment being known as anodizing. The parts to be treated are supported from suspension devices which also carry current, and the parts are in this way passed through a number of treatment baths, e.g. degreasing baths, rinsing baths, and anodizing baths.

Use has been made for suspending large numbers of small parts of a frame that consists of an electrically-conductive supporting main structure to which are fitted, as holders for the parts, electrically-conductive contact springs which are arranged in pairs. Each pair of springs functions to secure a part and to supply electric current thereto. The main structure is secured to a bar mounted above the baths.

This frame, however, suffers from the disadvantage that the pairs of contact springs are normally designed to suit a particular dimension of the part to be treated, and a pair of contact springs will only hold parts, of which the dimensions deviate only slightly from the particular value. This arrangement necessitates a new frame for parts whose critical dimensions vary to a greater extent. Furthermore, as the contact springs which function to carry current and to secure the parts to be treated become slightly worn, their ability to grip the parts satisfactorily and to provide good electrical contact is progressively reduced. Because of this slight wear, it also becomes impossible to fit the parts to be treated on the frame by mechanical means, since upon becoming worn, the contact springs are displaced from their original positions and the dimensional precision which is a prerequisite to any mechanized loading of the frames is lost.

SUMMARY OF THE INVENTORY Accordingly, it is an object of the present invention to 3,785,952 Patented Jan. 15, 1974 provide a frame for supportingly securing a large number of small parts having a circular edge or perforation parallel with a supporting surface while the parts are subjected to electro-deposition treatment, the frame being suitable on the one hand for carrying large numbers of parts having greatly differing edge-to-edge dimensions or perforation diameters and on the other for mechanical loading of the parts to be treated.

According to the present invention, this object is achieved by the main structure comprising at least one electrically conducting metal web and by each holder consisting of three non-electrically conducting rods which converge toward a point and which engage the circular edge and the perforation, respectively, of a part to be treated, and at least one resilient rail pressing the holders carrying the parts to be treated toward the metal web.

BRIEF DESCRIPTION OF THE DRAWING Novel features and advantages of the present invention, in addition to those mentioned above will become apparent to those skilled in the art from a reading of the following detailed description in conjunction with the accompanying drawing wherein similar reference characters refer to similar parts and in which:

FIG. 1 is an elevational view of a simple embodiment of a support for mounting small parts having circular perforations in an electroplating process, according to the present invention;

F FIG. 2 is a sectional view taken along line 22 of FIG. 3 is a plan view of another embodiment of the pcriesent invention for supporting parts having circular e ges;

FIG. 4 is a plan view of another embodiment of the present invention including product holders arranged in pairs; and

FIG. 5 is a plan view of still another embodiment of the present invention including holders on opposite sides of an electrically conductive Web.

DETAILED DESCRIPTION OF THE INVENTION Referring in more detail to FIGS. 1 and 2, a part 1 to be treated includes a circular opening or perforation 8 parallel to a supporting surface 9 to which is secured an electrically conductive metal web 2. The part 1 is pressed against the web 2 with the aid of a holder 3 and a resilient rail 4. The holder 3 consists of three non-conductive rods converging towards a point and extending into the circular perforation 8 in the part 1. The holder 3 is made of a non-conductive acid-resisting material, e.g. polypropylene or polycarbonate, and makes contact with the part 1 at three points. With such an arrangement the holder is capable of supporting different parts having perforations of greatly differing diameters. The holder 3 is not subjected to any wear and is suitable for mechanically receiving the part 1 by mechanized loading operations. The resilient rail 4 consists of a core of resilient e'lastomerit: substance or of a flexible tube made of such material and filled with air or some other gas. The core or tube is partly surrounded by a piece of curved sheet metal. The outside of the resilient rail 4 is protected against the effects of the contents of the baths into which it is inserted by an acid-resisting plastic material, for example, polytetrafluoroethylene.

The metal web 2 which performs the function of the supporting main structure, and in this instance is of U- shaped cross section, can be directly connected to the bar for carrying the products (not illustrated). In other instances the frame 9 functions to interconnect the metal webs 2 and bar for carrying the products. A plurality of parallel metal web 2 could, however, also be combined to form a metallic grid, it then being necessary to extend only two of the metal webs and to connnect them to the bar. Any metal normally used for these purposes can be employed as a material for the metal webs 2. The wear of the metal webs 2 is reduced as compared with that ccurring in the known suspension devices by pressing the parts 1 to be treated against constantly changing contact points. Also, these contact areas of the metal webs can be readily reconditioned in a fully mechanical mannner by grinding.

In the arrangement shown in FIG. 3, a part to be treated has a circular edge parallel with the supporting surface. The part 5 is pressed against the metal web 2 with the aid of a holder 3 and a resilient rail 4. In this case, the holder 3 engages the circular edge 10 of the part 5 by its three diverging rods and likewise at a point along each of the rods which can vary greatly in position depending upon the diameter of the circular edge 10.

FIG. 4 shows a further arrangement in which two holders 3 are connected to a clamping rail 6 which is pressed against two metal Webs 2 with the aid of a resilient rail 4. This arrangement is illustrated for the case where parts 5 having a circular edge 10 are to be treated. Corresponding clamping rails can, of course, also be designed for products such as parts 1 having circular perforations 8.

In the arrangement shown in FIG. 5, a metal web 7 is loaded from two opposite sides with parts 5 carried by holders 3. The holders are pressed against the web 7 with the aid of resilient rails 4. In this case, parts 1 having circular perforations 8 can be fitted instead of the parts 5 having circular edges 10. As shown in FIGS. 1 and 2 the tips of the holders 3 would then project into the circular perforations 8.

Also, the arrangements illustrated in FIGS. 4 and 5 can be combined, two metal webs 7 then each being loaded from two sides with parts to be treated which are carried by holders connected in pairs to clamping rails 6.

The frames according to the invention which enable the parts under treatment to be moved mechanically insure that for the like parts the distances between the metal web and the holder are always the same. As a result the applied pressure is always the same. This uniformly applied pressure results in an improved quality of the parts subjected to electro-deposition treatments.

What is claimed is:

1. A frame for supportingly securing a number of small parts having a circular edge or perforation parallel with a supporting surface while the parts are subjected to electrodeposition treatment, the frame comprising an electrically conductive main structure and holders for each part to be treated, the main structure including at least one electrically conductive metal web and each holder comprising a plurality of non-electrically conducting rods which converge towards a point and which engage the circular edge or perforation of a part to be treated, and at least one resilient rail constructed and arranged to press the holders carrying the parts to be treated against the metal web.

2. A frame as in claim 1 wherein the point of the converging holder rods extends into the circular perforation of the part to be treated.

3. A frame as in claim 1 wherein the diverging holder rods engage the circular edge of the part to be treated.

4. A frame as in claim 1 wherein the holders are connected in pairs to a clamping rail.

5. A frame as in claim 2 wherein the holders are connected in pairs to a clamping rail.

6. A frame as in claim 3 wherein the holders are connected in pairs to a clamping rail.

7. A frame as in claim 1 including a pair of resilient rails on opposite sides of a single conductive metal Web with holders between the resilient rails and the web.

8. A frame as in claim 2 including a pair of resilient rails on opposite sides of a single conductive metal web with holders between the resilient rails and the web.

9. A frame as in claim 3 including a pair of resilient rails on opposite sides of a single conductive metal web with holders between the resilient rails and the web.

10. A frame as in claim 4 including a pair of resilient rails on opposite sides of a single conductive metal web with holders between the resilient rails and the web.

11. A frame as in claim 5 including a pair of resilient rails on opposite sides of a single. conductive metal web with holders between the resilient rails and the web.

12. A frame as in claim 6 including a pair of resilient rails on opposite sides of a single conductive metal web with holders between the resilient rails and the web.

13. A frame as in claim 1 wherein a plurality of metal webs are combined to form a metal grid.

14. A frame as in claim 2 wherein a plurality of metal webs are combined to form a metal grid.

15. A frame as in claim 3 wherein a plurality of metal webs are combined to form a metal grid.

16. A frame as in claim 4 wherein a plurality of metal webs are combined to form a metal grid.

17. A frame as in claim 5 wherein a plurality of metal webs are combined to form a metal grid.

18. A frame as in claim 6 wherein a plurality of metal webs are combined to form a metal grid.

19. A frame as in claim 7 wherein a plurality of metal Webs are combined to form a metal grid.

20. A frame as in claim 8 wherein a plurality of metal webs are combined to form a metal grid.

21. A frame as in claim 9 wherein a plurality of metal webs are combined to form a metal grid.

22. A frame as in claim 10 wherein a plurality of metal webs are combined to form a metal grid.

23. A frame as in claim 11 wherein a plurality of metal webs are combined to form a metal grid.

24. A frame as in claim 12 wherein a plurality of metal webs are combined to form a metal grid.

References Cited UNITED STATES PATENTS 3,290,238 12/ 1966 Wierwille 204-297 W FOREIGN PATENTS 210,719 6/1909 Germany 204-297 W 763,660 4/1952 Germany 204-297 W F. C. EDMUNDSON, Primary Examiner 

